The present disclosure relates to a phosphor sheet containing a phosphor that fluoresces when irradiated with light, and a light emitting unit including the phosphor sheet, and a display unit including the phosphor sheet.
In general, a liquid crystal display includes a backlight light source that illuminates the entire liquid crystal panel from the back. Recently, the liquid crystal display has been increased in size, reduced in thickness and weight, or increased in life. Along with this, and in light of improvement of moving picture characteristics by flashing control, attention has been focused on a light emitting unit in which a plurality of light emitting diodes (LEDs) are provided on a substrate for surface emission. In such a light emitting unit, the following techniques are used to extract white light.
In a first technique, three colors of LEDs emitting light of R (red), G (green), and B (blue) are arranged, and when the LEDs are simultaneously turned on, the three colors of light are synthesized and white light is produced. In a second technique, for example, a blue LED is enclosed by a phosphor-containing resin so that blue light is color-converted into white light. Such a structure where the blue LED is enclosed by the phosphor-containing resin is called white LED.
Alternatively, as a third technique, there is proposed a technique where a phosphor-containing sheet, such as a sheet including a phosphor-containing resin sandwiched by sheet substrates or a sheet including a phosphor-containing resin formed into a sheet shape, is used to perform color conversion using blue LED (for example, see Japanese Unexamined Patent Application Publication No. 2013-32515). In addition, there is proposed a structure including a phosphor-containing resin sandwiched by two glass plates.